Venous thromboembolism and ethnicity

Epidemiology and management of massive, sub-massive, and non-massive pediatric pulmonary embolism: a systematic reviews

OBJECTIVE

To evaluate the current evidence on the diagnosis, management, and outcomes of pediatric pulmonary embolism (PE) across varying severity classifications, including massive, submassive, and non-massive presentations.

METHODS

A systematic review was conducted following PRISMA guidelines. Searches were performed in PubMed, Scopus, Web of Science, and Cochrane databases up to February 17, 2024. Eligible studies included pediatric and adolescent patients (≤ 21 years) with confirmed PE diagnoses. Risk of bias was assessed using the NIH tool.

RESULTS

Six studies involving 258 pediatric patients with massive, submassive, or non-massive PE were included. Most patients were adolescents, with a mean age of 14.1 years and a predominance of females (62-66%). Risk factors included obesity, oral contraceptive use, thrombophilia, and autoimmune conditions. Computed tomography pulmonary angiography (CTPA) was the most frequently used diagnostic modality, showing varied lobar, segmental, and subsegmental involvement. Management strategies ranged from anticoagulation to catheter-directed thrombolysis and surgical thrombectomy. Outcomes varied by severity, with massive PE cases showing higher mortality and complications compared to submassive and non-massive cases.

CONCLUSION

Pediatric PE requires tailored risk stratification and management strategies to optimize outcomes. Delays in diagnosis and severe disease presentations contribute to higher morbidity and mortality. Future research should focus on standardized severity classifications, novel diagnostic modalities, and comparative assessments of therapeutic interventions to enhance outcomes in this population.

Quantitative methods to improve bivalirudin dosing in pediatric cardiac ICU patients

BACKGROUND

A gap in knowledge exists related to optimal bivalirudin dosing in children. The purpose of our analysis is to use quantitative methods and baseline data to quickly predict the optimal therapeutic bivalirudin dose for children.

METHODS

We developed an internal database of pediatric patients on ECMO or VAD, including baseline patient information, bivalirudin doses, and partial thromboplastin time (PTT) measurements throughout the treatment period. We fit an analysis of covariance (ANCOVA) model to the baseline data to determine the best predictors of therapeutic bivalirudin dose. We used five-fold cross-validation to ensure the model was not overfitting to any specific data subset.

RESULTS

The most notable variables that were statistically significant (p < .05) were: the primary use of bivalirudin for heart failure prophylaxis, no complications before bivalirudin administration, other reasons for bivalirudin use, other race (including Asian, pacific islander, and native American), Hispanic or Latinx ethnicity, primary diagnosis of heart failure, and primary diagnosis of myocarditis. To compare our model-predicted dose and the actual starting dose administered to the patients, we looked at how far off each of those was from the therapeutic dose. The mean of absolute differences was 0.28 mg/kg/hr for the administered starting dose and 0.23 mg/kg/hr for the model-predicted dose; therefore, the model results in an improvement of 18% in the difference from the therapeutic dose.

CONCLUSION

Our model provides an initial framework for determining a starting bivalirudin dose that takes into account patient demographic information and baseline admission data.

Association of Fibrinogen Aα Thr312Ala (rs6050) Polymorphism with Venous Thrombosis and Chronic Thromboembolic Pulmonary Hypertension: A Meta-Analysis

BACKGROUND

Venous thromboembolism (VTE) comprises deep vein thrombosis (DVT) and pulmonary embolism (PE). Chronic thromboembolic pulmonary hypertension (CTEPH) typically arises from acute pulmonary embolism. The pathogenesis of them involves multiple risk factors such as genetic predisposition. However, the findings from these studies are not entirely consistent. This study aims to investigate the association between FGA rs6050 polymorphism and susceptibility to thrombotic diseases.

METHODS

We searched PubMed, OVID, Web of Science, Academic Search Ultimate, CNKI, and Wan Fang database. To assess the strength of associations, we calculated pooled odds ratios (ORs) and 95% confidence intervals (CIs) in different genetic models. Additionally, subgroup analyses, sensitivity analysis, and assessment of publication bias were also carried out.

RESULTS

A total of 11 studies, including 9 reported results on VTE (3856 individuals [1545 cases]) and 3 on CTEPH (761 participants [350 cases]), revealed a significant association between the rs6050 polymorphism and susceptibility to both VTE and CTEPH. The A allele was consistently linked to an elevated risk of VTE across all genetic models (allele, homozygote, heterozygote, recessive, and dominant model), while it was also associated with an increased risk of CTEPH under all genetic models excluding the recessive model. Furthermore, subgroup analysis among ethnic groups revealed a significant association between rs6050 polymorphisms and VTE in both Caucasians and Asians under all genetic models. In Africans, the association with VTE was only observed for rs6050 polymorphisms in dominant and heterozygous models.

CONCLUSIONS

The FGA rs6050 polymorphism is positively associated with susceptibility to VTE and CTEPH.

Lessons learned from setting up a hospital-based national registry for venous thromboembolic disorders in India

Introduction

Health registries are instrumental in tracking trends in the number of people with diseases, monitoring treatment options, and assessing health outcomes. This research examines the challenges of establishing and maintaining a venous thromboembolism (VTE) registry in the Indian context.

Methods

A mixed-method approach with purposive sampling was conducted to capture the challenges faced by individuals playing key roles in the establishment and operation of the national registry on VTE. This study focused on 10 questions related to technological infrastructure, resource optimization, data collection and management, coordination and collaboration, regulatory compliance, and political influences and were documented using a semi-structured questionnaire and telephonic interviews.

Results

Technological, recruitment, and follow-up challenges were prominently highlighted with issues related to data entry, system glitches, changes to the data entry forms, and potential participant reluctance.

Conclusion

Findings from this study highlight the multifaceted challenges experienced during the establishment of a national registry on VTE. By integrating insights from our findings into suggestions, this discussion reflects the specific challenges faced by the research project and offers evidence-based strategies for mitigating these challenges.

Advancements in the interventional therapy and nursing care on deep vein thrombosis in the lower extremities

This review examines recent advancements in interventional treatments and nursing care for lower extremity deep vein thrombosis (DVT), highlighting significant innovations and their clinical applications. It discusses the transition to novel anticoagulants such as Direct Oral Anticoagulants, which offer a safer profile and simplified management compared to traditional therapies. Mechanical interventions, including balloon angioplasty and venous stenting, are detailed for their roles in improving immediate and long-term vascular function in acute DVT cases. Furthermore, the use of image-guided techniques is presented as essential for enhancing the accuracy and safety of DVT interventions. Additionally, this study outlines advances in nursing care strategies, emphasizing comprehensive preoperative and postoperative evaluations to optimize patient outcomes. These evaluations facilitate tailored treatment plans, crucial for managing the complex needs of DVT patients. Long-term care strategies are also discussed, with a focus on patient education to ensure adherence to treatment protocols and to prevent recurrence. The synthesis aims to inform healthcare professionals about cutting-edge practices in DVT management, promoting a deeper understanding of how these advancements can be integrated into clinical practice. It also underscores the necessity for ongoing research to address challenges such as cost-effectiveness and patient compliance, ensuring that future treatments are both accessible and effective.

Thrombosis events in Chinese patients with newly diagnosed multiple myeloma

A high risk of thrombosis is seen in patients with newly diagnosed multiple myeloma (NDMM), particularly those treated with immunomodulatory drugs (IMiDs). Large cohorts addressing the thrombosis issue of NDMM patients in Asia are lacking. We retrospectively analyzed the clinical information of NDMM patients diagnosed in Zhongshan Hospital Fudan University, a national medical center, from January 2013 to June 2021. Death and thrombotic events (TEs) were the endpoints. To investigate risk factors for TEs, the Fine and Gray competing risk regression models were created, in which unrelated deaths were labeled as competing risk events. A total of 931 NDMM patients were recruited in our study. The median follow-up was 23 months [interquartile range (IQR): 9-43 months]. Forty-two patients (4.51%) developed TEs, including 40 cases (4.30%) of venous thrombosis and 2 cases (0.21%) of arterial thrombosis. The median time from taking first-line treatment to TEs occurrence was 2.03 months (IQR: 0.52-5.70 months). The cumulative incidence of TEs was higher in patients treated with IMiDs than in those without IMiDs (8.25 vs. 4.32%, p = 0.038). There was no difference in the incidence of TEs between lenalidomide-based and thalidomide-based groups (7.80 vs. 8.84%, p = 0.886). Besides, TEs occurrence did not adversely affect OS (p = 0.150) or PFS (p = 0.210) in MM patients. Chinese NDMM patients have a lower incidence of thrombosis than those in western countries. The risk of thrombosis was particularly increased in patients treated with IMiDs. TEs were not associated with inferior progression-free survival or overall survival.

Detection of Exon 10 Mutation (rs6020) in Factor V Gene in Sudanese patients with Deep Vein Thrombosis.. [DOI: 10.21203/rs.3.rs-2500709/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: Deep vein thrombosis (DVT), a subgroup of venous thromboembolism (VTE), is one of the leading causes of morbidity and mortality globally, accounting for 60,000-100,000 fatalities per year. It affects around 0.1 percent of the population each year. In Sudanese patients with DVT, this study looked for probable harmful single nucleotide polymorphisms in exon 10 of the factor V gene. Method: Thirty blood samples were obtained from previously diagnosed DVT patients at Omdurman teaching hospital throughout the period of 16 August to 25 October 2018, as part of a descriptive cross-sectional research in Khartoum state. Exon 10 was amplified by PCR using sequence-specific primers after DNA was extracted using the guanidine chloride procedure. The fifteen best bands' PCR products were sequenced in both directions (BGI Company). Bioinformatics techniques were used to examine the sequences (Finch TV, BLAST, and Codon Code alignment). Result: The presence of a missense mutation (rs6020) in the factor V Leiden gene was discovered in 40% (6/15) of the patients in this investigation. In five cases, this mutation was heterozygous, whereas in one patient, it was homozygous. In the other nine cases, no mutations were found. Conclusion: rs6020 is more prevalent in the Sudanese population than other types of mutations. rs6020 polymorphism has a strong association with deep vein thrombosis in the Sudanese population. Further investigation of this mutation amongst larger Sudanese population is required in order to support this finding as well as to understand its clinical significance.

Race does matter: venous thromboembolism in trauma patients with isolated severe pelvic fractures

PURPOSE

Studies in non-trauma populations have shown that Black patients have a higher risk of venous thromboembolism (VTE) compared to other races. We sought to determine whether this association exists in trauma patients. The incidence of VTE is particularly high following severe pelvic fractures. To limit confounding factors associated with additional injuries, we examined patients with isolated blunt severe pelvic fractures.

METHODS

The TQIP database (2013-2017) was queried for all patients who sustained isolated blunt severe pelvic fractures (AIS ≥ 3) and received VTE prophylaxis (VTEp) with either unfractionated heparin or low molecular weight heparin. The study groups were Asian, Black, and White race as defined by TQIP. The primary outcome was differences in the rate of thromboembolic events.

RESULTS

A total of 9491 patients were included in the study. Of these, 232 (2.4%) were Asian, 1238 (13.0%) Black, and 8021 (84.5%) White. There was no significant difference in the distribution of pelvis AIS 3,4,5 between the groups. Black patients had a significantly higher incidence of VTE, DVT and PE compared to Asians and Whites. After adjusting for differences between the groups, Black patients had higher odds of developing pulmonary embolism (OR 1.887, 95% CI 1.101-3.232, p = 0.021) compared to White patients.

CONCLUSIONS

In this nationwide study of trauma patients with severe pelvic fractures, Black patients were more likely to develop pulmonary embolism compared to White patients. Further research to identify the determinants of racial disparities in trauma-related VTE is warranted, to target interventions that can improve VTE outcomes for all patients.

Intermediate-dose versus low-dose low-molecular-weight heparin in pregnant and post-partum women with a history of venous thromboembolism (Highlow study): an open-label, multicentre, randomised, controlled trial

BACKGROUND

Pregnancy-related venous thromboembolism is a leading cause of maternal morbidity and mortality, and thromboprophylaxis is indicated in pregnant and post-partum women with a history of venous thromboembolism. The optimal dose of low-molecular-weight heparin to prevent recurrent venous thromboembolism in pregnancy and the post-partum period is uncertain.

METHODS

In this open-label, randomised, controlled trial (Highlow), pregnant women with a history of venous thromboembolism were recruited from 70 hospitals in nine countries (the Netherlands, France, Ireland, Belgium, Norway, Denmark, Canada, the USA, and Russia). Women were eligible if they were aged 18 years or older with a history of objectively confirmed venous thromboembolism, and with a gestational age of 14 weeks or less. Eligible women were randomly assigned (1:1), before 14 weeks of gestational age, using a web-based system and permuted block randomisation (block size of six), stratified by centre, to either weight-adjusted intermediate-dose or fixed low-dose low-molecular-weight heparin subcutaneously once daily until 6 weeks post partum. The primary efficacy outcome was objectively confirmed venous thromboembolism (ie, deep-vein thrombosis, pulmonary embolism, or unusual site venous thrombosis), as determined by an independent central adjudication committee, in the intention-to-treat (ITT) population (ie, all women randomly assigned to treatment). The primary safety outcome was major bleeding which included antepartum, early post-partum (within 24 h after delivery), and late post-partum major bleeding (24 h or longer after delivery until 6 weeks post partum), assessed in all women who received at least one dose of assigned treatment and had a known end of treatment date. This study is registered with ClinicalTrials.gov, NCT01828697, and is now complete.

FINDINGS

Between April 24, 2013, and Oct 31, 2020, 1339 pregnant women were screened for eligibility, of whom 1110 were randomly assigned to weight-adjusted intermediate-dose (n=555) or fixed low-dose (n=555) low-molecular-weight heparin (ITT population). Venous thromboembolism occurred in 11 (2%) of 555 women in the weight-adjusted intermediate-dose group and in 16 (3%) of 555 in the fixed low-dose group (relative risk [RR] 0·69 [95% CI 0·32-1·47]; p=0·33). Venous thromboembolism occurred antepartum in five (1%) women in the intermediate-dose group and in five (1%) women in the low-dose group, and post partum in six (1%) women and 11 (2%) women. On-treatment major bleeding in the safety population (N=1045) occurred in 23 (4%) of 520 women in the intermediate-dose group and in 20 (4%) of 525 in the low-dose group (RR 1·16 [95% CI 0·65-2·09]).

INTERPRETATION

In women with a history of venous thromboembolism, weight-adjusted intermediate-dose low-molecular-weight heparin during the combined antepartum and post-partum periods was not associated with a lower risk of recurrence than fixed low-dose low-molecular-weight heparin. These results indicate that low-dose low-molecular-weight heparin for thromboprophylaxis during pregnancy is the appropriate dose for the prevention of pregnancy-related recurrent venous thromboembolism.

FUNDING

French Ministry of Health, Health Research Board Ireland, GSK/Aspen, and Pfizer.

Tranexamic acid reduces postoperative blood loss in Chinese pediatric patients undergoing cardiac surgery: A PRISMA-compliant systematic review and meta-analysis

BACKGROUND

Tranexamic acid has been increasingly used for blood conservation in cardiac surgery. However, the evidence supporting the routine use of tranexamic acid in Chinese pediatric patients undergoing cardiac surgery remains weak. This meta-analysis aimed to systematically review the efficacy of tranexamic acid when applying to Chinese pediatric patients undergoing cardiac surgery.

PARTICIPANTS

Chinese pediatric patients undergoing cardiac surgery.

INTERVENTIONS

Tranexamic acid or control drugs (saline/blank).

METHODS

PUBMED, Cochrane Library, EMBASE, China National Knowledge Infrastructure (CNKI), Wanfang Data, and VIP Data till May 4, 2021, database search was updated on August 1. Primary outcomes of interest included postoperative bleeding, allogeneic transfusion, and reoperation for bleeding. Secondary outcomes of interest included postoperative recovery. For continuous/dichotomous variables, treatment effects were calculated as weighted mean difference (WMD)/odds ratio and 95% confidence interval.

RESULTS

A database search yielded 15 randomized controlled trials including 1641 patients, where 8 studies were allocated into non-cyanotic congenital group, 5 were allocated into cyanotic congenital group, and the other 2 were allocated into combined cyanotic/non-cyanotic group. This meta-analysis demonstrate that tranexamic acid administration can reduce the postoperative 24 hours blood loss in non-cyanotic, cyanotic, and combined cyanotic/non-cyanotic patients, the red blood cell transfusion in non-cyanotic and cyanotic patients, and the fresh frozen plasma transfusion in non-cyanotic and combined cyanotic/non-cyanotic patients.

CONCLUSION

This meta-analysis demonstrates that tranexamic acid is highly effective in reducing the blood loss in Chinese pediatric cardiac surgery, but it behaves poorly when it comes to the transfusion requirement. To further confirm this, more well-designed and adequately-powered randomized trials are needed.

Association between Hyperosmolar Hyperglycemic State and Venous Thromboembolism in Diabetes Patients: A Nationwide Analysis in Taiwan

Background: Previous studies in Western countries have shown that a hyperosmolar hyperglycemic state (HHS) is associated with an increased risk of venous thromboembolism (VTE); in these cases, prophylactic anticoagulant treatment is suggested. However, the association between HHS and VTE in Asian populations remains undetermined. Therefore, we aimed to evaluate whether HHS is associated with an increased risk of VTE in diabetic Taiwanese patients. Methods: This nationwide, population-based, retrospective cohort study was conducted using the Taiwan National Health Insurance Research Database. We enrolled a total of 4,723,607 admission records of patients with diabetes diagnosed with one or more of seven common diseases (pneumonia, urinary tract infection, sepsis, heart disease, stroke, malignancy, and respiratory tract disease) between 2001 and 2018 in Taiwan. The patients were divided into two groups based on the presence (n = 46,000) or absence (n = 4,677,607) of HHS. We estimated the adjusted odds ratio (aOR) for developing VTE within 90 days after the index hospitalization using multivariable logistic regression with generalized estimating equations accounting for repeated measures. Results: Overall, patients admitted with HHS had a similar risk of VTE compared with those admitted without HHS (408/46,000 vs. 39,345/4,677,607; aOR = 1.06, 95% CI: 0.97–1.17, p = 0.190). A similar non-significant association between HHS and VTE was found regardless of age and sex subgroups. Conclusions: There was no significant association between HHS and overall VTE risk in patients with diabetes in Taiwan. The results of our study may not support the use of prophylactic anticoagulant therapy in diabetic Taiwanese patients with HHS.

Clinical characteristics and disease course of splanchnic vein thrombosis in gastrointestinal cancers: A prospective cohort study

PURPOSE

Splanchnic vein thrombosis (SpVT) in solid tumors has not been well investigated. Therefore, the treatment guidelines for SpVT are not well established. We aimed to conduct this prospective study to investigate the clinical characteristics and risk factors influencing survival in patients with gastrointestinal cancer with SpVT.

MATERIALS AND METHODS

Fifty-one patients with gastrointestinal cancer diagnosed with SpVT were prospectively enrolled. The clinical characteristics and courses of SpVT were analyzed.

RESULTS

SpVT occurred in various clinical situations (at the time of initial cancer diagnosis or tumor recurrence after curative therapy, in the postoperative period, during chemotherapy, or in the period of end-of-life care). Among the total patients, 90.2% had no SpVT-related symptoms at initial SpVT diagnosis, and 82.4% did not receive any anticoagulation therapy. The clinical course of SpVT during the follow-up varied: (1) spontaneous resorption without any anticoagulation (47.1%), (2) resorption with anticoagulation (3.9%), (3) persistent thrombosis without progression (17.6%), and (4) SpVT extension (31.4%). Although the SpVT showed extension in some cases, most of them did not cause symptoms or had little impact on the patient's cancer treatment course. During the follow-up period, 23 patients died, all of which were caused by tumor progression. In the multivariable analysis, performance status and clinical situation at the time of SpVT diagnosis were significant prognostic factors.

CONCLUSIONS

Clinicians could adopt a strategy of close observation for incidentally detected SpVT in patients with gastrointestinal cancer. Anticoagulation should be considered only for SpVT cases selected strictly, weighing the risks and benefits.

Recurrent Spontaneous Miscarriage: a Comparison of International Guidelines

While roughly 30% of all women experience a spontaneous miscarriage in their lifetime, the incidence of recurrent (habitual) spontaneous miscarriage is 1 – 3% depending on the employed definition. The established risk factors include endocrine, anatomical, infection-related, genetic, haemostasis-related and immunological factors. Diagnosis is made more difficult by the sometimes diverging recommendations of the respective international specialist societies. The present study is therefore intended to provide a comparison of existing international guidelines and recommendations. The guidelines of the ESHRE, ASRM, the DGGG/OEGGG/SGGG and the recommendations of the RCOG were analysed. It was shown that investigation is indicated after 2 clinical pregnancies and the diagnosis should be made using a standardised timetable that includes the most frequent causes of spontaneous miscarriage. The guidelines concur that anatomical malformations, antiphospholipid syndrome and thyroid dysfunction should be excluded. Moreover, the guidelines recommend carrying out pre-conception chromosomal analysis of both partners (or of the aborted material). Other risk factors have not been included in the recommendations by all specialist societies, on the one hand because of a lack of diagnostic criteria (luteal phase insufficiency) and on the other hand because of the different age of the guidelines (chronic endometritis). In addition, various economic and consensus aspects in producing the guidelines influence the individual recommendations. An understanding of the underlying decision-making process should lead in practice to the best individual diagnosis and resulting treatment being offered to each couple.

Hypercoagulability in Vestibular Schwannoma Surgery

OBJECTIVE

Patients with vestibular schwannoma who harbor a genetic predisposition for venous thromboembolism require special consideration when determining optimal therapeutic management. The primary objective of the current study was to provide recommendations on treatment of hypercoagulable patients with vestibular schwannoma through a case series and review of the literature.

PATIENTS

Two patients who underwent resection of vestibular schwannomas.

INTERVENTIONS

Surgical resection and diagnostic testing.

MAIN OUTCOME MEASURES

Postoperative venous thromboses.

RESULTS

One patient who underwent resection of vestibular schwannoma and suffered several postoperative thrombotic complications consistent with a clinical thrombophilia. One patient with known Factor V Leiden deficiency who underwent resection of vestibular schwannoma followed by postoperative chemoprophylaxis with a direct factor Xa inhibitor and experienced an uneventful postoperative course.

CONCLUSIONS

In patients with a known propensity for venous thromboembolism, the skull base surgeon should consider nonsurgical management. If the patient undergoes surgical resection, we recommend careful effort to minimize trauma to the sigmoid sinus. In addition, the surgeon may consider retrosigmoid or middle fossa approaches. Best practice recommendations include the use of pneumatic compression devices, early ambulation, and consideration of postoperative prophylactic anticoagulation in patients with a known genetic predisposition.

Large Vessel Occlusion Secondary to COVID-19 Hypercoagulability in a Young Patient: A Case Report and Literature Review

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) initially most appreciated for its pulmonary symptoms, is now increasingly recognized for causing multi-organ disease and stroke in the setting of a hypercoagulable state. We report a case of 33-year-old African American woman with COVID-19 who developed acute malignant middle cerebral artery infarction due to thromboembolic occlusion of the left terminal internal carotid artery and middle cerebral artery stem. Mechanical thrombectomy was challenging and ultimately unsuccessful resulting in limited reperfusion of <67% of the affected vascular territory, and thrombectomized clot was over 50 mm in length, at least three times the average clot length. The final stroke size was estimated at 224 cubic centimeters. On admission her D-dimer level was 94,589 ng/mL (normal 0-500 ng/ml). Throughout the hospitalization D-dimer decreased but never reached normal values while fibrinogen trended upward. Hypercoagulability panel was remarkable for mildly elevated anticardiolipin IgM of 16.3 MPL/mL (normal: 0-11.0 MPL/mL). With respect to remaining stroke workup, there was no evidence of clinically significant stenosis or dissection in the proximal internal carotid artery or significant cardioembolic source including cardiomyopathy, atrial fibrillation, cardiac thrombus, cardiac tumor, valvular abnormality, aortic arch atheroma, or patent foramen ovale. She developed malignant cytotoxic cerebral edema and succumbed to complications. This case underscores the importance of recognizing hypercoagulability as a cause of severe stroke and poor outcome in young patients with COVID-19 and highlights the need for further studies to define correlation between markers of coagulopathy in patients with COVID-19 infection and outcome post stroke.

Carvalho M, Morishita E. Racial differences in protein S Tokushima and two protein C variants as genetic risk factors for venous thromboembolism

BACKGROUND

Racial differences in genetic risk factors for venous thromboembolism (VTE) are elucidated, with factor V Leiden and prothrombin G20210A being prevalent among the Caucasian population but rare among non-Caucasians.

OBJECTIVES

To assess the worldwide distribution of three gene polymorphisms previously identified as genetic risk factors among East Asian subpopulations: protein S (PS) Tokushima (p.Lys196Glu), protein C (PC) p.Arg189Trp, and PC p.Lys193del.

METHODS

An international collaborative study group of seven centers in five countries-Japan, South Korea, Singapore, Hungary, and Brazil-was created, and genotype analyses were performed. A total of 2850 unrelated individuals (1061 patients with VTE and 1789 controls) were included.

RESULTS

PS Tokushima was confined to Japanese patients with VTE (allele frequency, 2.35%) and controls (1.12%), with an odds ratio (OR) of 2.15 (95% confidence interval, 1.16-3.99). PC p.Arg189Trp carriers were prevalent among Chinese and Malay patients with VTE in Singapore, with allele frequencies of 10.53% and 22.73%, respectively. Carriers of PC p.Lys193del were identified among Japanese and Korean patients with VTE (0.87% and 2.35%, respectively) and controls (0.36% and 1.07%, respectively), with the OR for VTE not being significant, and Chinese patients with VTE in Singapore (5.26%). In contrast, no carriers of PS Tokushima and two PC gene variants were found among patients with VTE or controls from Hungary, Brazil, or Indians in Singapore.

CONCLUSION

The three variants were prevalent among East and Southeast Asians, having some differences in geographic distribution, but were absent among Caucasian subpopulations and Brazilians.

Venous Thromboembolism in Children: From Diagnosis to Management

Venous thromboembolism (VTE) in children is a rare occurrence, although in recent decades we have seen an increase due to several factors, such as the rise in survival of subjects with chronic conditions, the use of catheters, and the increased sensitivity of diagnostic tools. Besides inherited thrombophilia, acquired conditions such as cardiovascular diseases, infections, chronic disorders, obesity and malignancy are also common risk factors for paediatric VTE. The treatment of paediatric VTE consists of the use of heparins and/or vitamin K antagonists to prevent dissemination, embolization, and secondary VTE. Randomized clinical trials of direct oral anticoagulants in paediatric VTE are ongoing, with the aim to improve the compliance and the care of patients. We reviewed the physiological and pathological mechanisms underlying paediatric thrombosis and updated the current diagnosis and treatment options.

Laboratory monitoring of rivaroxaban in Chinese patients with deep venous thrombosis: a preliminary study

Background

Rivaroxaban, a novel oral anticoagulant drug, is widely used in clinical practice. There is no standardized laboratory monitoring for rivaroxaban, and its plasma concentration in Chinese patients with deep vein thrombosis is unclear. The rivaroxaban concentrations in human plasma and determine the steady-state concentration of rivaroxaban in patients with deep vein thrombosis are needed.

Methods

An ultra-high-performance liquid chromatography with mass spectrometric detection method was developed. Chromatographic separation was performed on a Waters BEH C18 column with isocratic elution using a mobile phase composed of acetonitrile and water. Quantitation of the analytes was performed using positive ionization mode and mass transitions of m/z 437.3 → m/z 145.0 and m/z 440.1 → m/z 145.0 for rivaroxaban and the internal standard, respectively. Blood samples were collected at 0 h and 2 h after patients took rivaroxaban for 7 days or more.

Results

The method was validated over the concentration range of 0.5 ~ 400 ng•mL^− 1 with a very low limit of quantification of 0.5 ng·mL^− 1, and the intra- and inter-day precision (RSD%) were < 15%. The range of the steady state concentration in patients that took 15 mg rivaroxaban twice daily, 10 mg twice daily, 20 mg once daily, 15 mg once daily, and 10 mg once daily were 168.5 ~ 280.1 ng•mL^− 1, 74.2 ~ 271.4 ng•mL^− 1, 25.7 ~ 306.8 ng•mL^− 1, 24.5 ~ 306.4 ng•mL^− 1, and 15.4 ~ 229.2 ng•mL^− 1, respectively.

Conclusions

The plasma rivaroxaban concentration in patients who took 10 mg rivaroxaban twice daily fluctuated less than that in patients who took 20 mg rivaroxaban once daily. The plasma concentration can be used for therapeutic drug monitoring for rivaroxaban.

Plasma phenotypes of protein S Lys196Glu and protein C Lys193del variants prevalent among young Japanese women

Protein S Tokushima (p.Lys196Glu) and two protein C gene variants (p.Arg189Trp, p.Lys193del) are hereditary thrombophilia in Japanese and Chinese populations, respectively; however, their diagnosis by plasma analyses is difficult because of the type II deficiency phenotype. Three gene variant genotypes were examined in young Japanese women (n = 231). Plasma total protein S activity and total protein S antigen levels were measured using a total protein S assay system, protein C and protein S activities by clot-based methods, and protein C and free protein S antigen levels by latex agglutination methods. protein S Tokushima (p.Lys196Glu) and protein C p.Lys193del variants were prevalent among participants with allele frequencies of 1.08 and 0.86%, respectively, whereas any carrier of protein C p.Arg189Trp variant was not identified. The plasma phenotype of the type II deficiency of protein S Tokushima heterozygotes was demonstrated by decreased total protein S activity with a normal total protein S antigen level; however, the protein C activities of protein C p.Lys193del heterozygotes were within reference intervals, whereas their protein C antigen levels were elevated. We compared the diagnostic accuracy of the total protein S activity/total protein S antigen ratio for identifying protein S Tokushima heterozygotes with that of the clot-based protein S activity/free protein S antigen ratio and found that sensitivity and specificity of 100% each was only achieved by the former. Protein S Tokushima and protein C p.Lys193del are prevalent among young Japanese women, and a plasma analysis using the total protein S assay system is more accurate than the clot-based protein S activity/free protein S antigen ratio for diagnosing protein S Tokushima carriers.

Racial and Ethnic Differences in Response to Anticoagulation: A Review of the Literature

INTRODUCTION

Anticoagulants are among the most frequently prescribed medications in the United States. Racial and ethnic disparities in incidence and outcomes of thrombotic disorders are well-documented, but differences in response to anticoagulation are incompletely understood.

OBJECTIVE

The objective of this review is to describe the impact of race and ethnicity on surrogate and clinical end points related to anticoagulation and discuss racial or ethnic considerations for prescribing anticoagulants.

METHODS

A PubMed and MEDLINE search of clinical trials published between 1950 and May 2018 was conducted using search terms related to anticoagulation, specific anticoagulant drugs, race, and ethnicity. References of identified studies were also reviewed. English-language human studies on safety or efficacy of anticoagulants reporting data for different races or ethnicities were eligible for inclusion.

RESULTS

Seventeen relevant studies were identified. The majority of major trials reviewed for inclusion either did not include representative populations or did not report on the racial breakdown of participants. Racial differences in pharmacokinetics, dosing requirements, drug response, and/or safety end points were identified for unfractionated heparin, enoxaparin, argatroban, warfarin, rivaroxaban, and edoxaban.

CONCLUSIONS

Race appears to influence drug concentrations, dosing, or safety for some but not all direct oral anticoagulants. This information should be considered when selecting anticoagulant therapy for nonwhite individuals.

Predicting venous thromboembolism risk from exomes in the Critical Assessment of Genome Interpretation (CAGI) challenges

Genetics play a key role in venous thromboembolism (VTE) risk, however established risk factors in European populations do not translate to individuals of African descent because of the differences in allele frequencies between populations. As part of the fifth iteration of the Critical Assessment of Genome Interpretation, participants were asked to predict VTE status in exome data from African American subjects. Participants were provided with 103 unlabeled exomes from patients treated with warfarin for non-VTE causes or VTE and asked to predict which disease each subject had been treated for. Given the lack of training data, many participants opted to use unsupervised machine learning methods, clustering the exomes by variation in genes known to be associated with VTE. The best performing method using only VTE related genes achieved an area under the ROC curve of 0.65. Here, we discuss the range of methods used in the prediction of VTE from sequence data and explore some of the difficulties of conducting a challenge with known confounders. In addition, we show that an existing genetic risk score for VTE that was developed in European subjects works well in African Americans.

Genetic profiling revealed an increased risk of venous thrombosis in the Hungarian Roma population

BACKGROUND

Besides modifiable risk factors, genetic susceptibility may also explain the high cardiovascular disease burden of the Roma population.

OBJECTIVES

Aim of this study was to define the genetic susceptibility of Hungarian Roma to venous thrombosis (VT) and comparing it to that of the general population.

METHODS

Fifty-two SNPs associated with VT (in F2, F5, F9, F11, F15, FGA, FGB, FGG, CYP4V2, KLKB1 and vWF) were selected and analyzed in the group of Roma (N = 962) and general (N = 1492) subjects collected by cross-sectional studies. Allele frequencies and genetic risk scores (GRS, unweighted and weighted) were computed for the study groups and compared to estimate the joint effects of SNPs.

RESULTS

The majority of the susceptible alleles were more prevalent in the Roma population, and both GRS and wGRS were found to be significantly higher in Roma than in the general population (GRS: 41.83 ± 5.78 vs. 41.04 ± 6.04; wGRS: 7.78 ± 1.28 vs. 7.46 ± 1.33, p = .001). Only 2.39% of subjects in the Roma population were in the bottom fifth of the wGRS (wGRS≤0.19) compared with 3.62% of those in the general population (p = .080); 2.88% of the general subjects were in the top fifth of the wGRS (wGRS≥10.02), while 4.26% of the Roma population were (p = .066).

CONCLUSION

In conclusion, the Roma population seems to have increased genetic susceptibility to VT. This might have important implications in the future in identifying possible new opportunities for targeted prevention and treatment for those subgroups in the populations who are at greater risk for VT development.

Utility of thrombophilia screening in pediatric renal transplant recipients

Thrombosis after kidney transplantation may result in catastrophic outcomes, including graft loss. Thrombophilia has been implicated in post-transplant thrombosis; data, however, are inconclusive on the impact of acquired and inherited thrombophilia and resultant thrombosis in renal graft recipients. We aimed to evaluate whether identifying children with thrombophilia during the pretransplant evaluation predicted post-transplant outcomes. We reviewed 100 kidney transplants performed in 100 children, aged 1-18 years, in a single-center retrospective study. Routine pretransplant comprehensive thrombophilia evaluation was completed. Thrombophilia was demonstrated in 36% patients (N = 36). TEs occurred in 11 patients before kidney transplant. Low PS and antithrombin were found in 9/86 (10.5%) and 2/89 (2.2%) children, respectively. Heterozygosity for FLV and PGM were found in 5/81 (6.2%) and 1/93(1.1%) children, respectively. A post-transplant thrombotic event occurred in 10 children (10%); six involved the renal transplant. The association between a history of a pretransplant thrombotic event and post-operative renal graft thrombosis approached, but did not reach significance (P = 0.071). There was no association between preoperative screening abnormalities and post-operative TEs. Graft loss due to a thrombotic event occurred in two patients; none had underlying thrombophilia. Our data suggest that the utility of universal, comprehensive preoperative thrombophilia testing is not beneficial in determining risk of post-operative graft thrombosis. Thrombophilia testing may be considered in a select population with a history of pretransplant thrombotic event.

Thromboembolic events in patients with advanced stage non-small cell lung cancer treated with platinum-based chemotherapy: a prospective observational study

Objectives

Cancer is frequently complicated by thromboembolic events (TEs). We aimed to determine the incidence of TEs in lung cancer patients treated with platinum-based chemotherapy and study patients’ baseline and treatment attributes correlating with its onset.

Materials and methods

Advanced lung cancer patients started on platinum-based chemotherapy were evaluated at baseline and during routine visits for the development of TEs. The duration of follow-up was 4 weeks from the last chemotherapy. A TE occurring between the first dose of chemotherapy and 4 weeks after the last dose was considered to be chemotherapy associated.

Results

Of the 165 patients on platinum chemotherapy who completed follow-up, TEs occurred in 4.8% (8 out of 165) patients. Among these, three patients had developed venous pulmonary thromboembolism and five patients had developed cerebral infarction, out of which four had arterial cerebral infarction and one patient had a superior sagittal sinus thrombosis. The majority of events (7 out of 8) occurred within 100 days of starting platinum chemotherapy. Overall, the median time until occurrence of TE was 48 days (range, 10–130 days). None of the presumed risk factors were found be associated with the occurrence of TEs on univariate analysis.

Conclusions

Advanced lung cancer patients on platinum chemotherapy are predisposed to thromboembolism due to many factors. Despite its lower incidence in our study, exclusion of patients with prior thrombosis suggests the incidence of de novo thrombosis, and hence raises a valid question of the need of thromboprophylaxis in a selected group of patients.

Immigration, region of origin, and the epidemiology of venous thromboembolism: A population-based study

BACKGROUND

Venous thromboembolism (VTE) epidemiology has been mainly studied in populations largely of European ancestry.

OBJECTIVES

To assess the epidemiology of VTE in immigrants to Ontario, Canada.

PATIENTS/METHODS

We conducted a population-based retrospective cohort study using linked health-care and administrative databases. We included 1 195 791 immigrants to Ontario and 1 195 791 nonimmigrants, matched on age, sex, and place of residence. The main exposure was ethnicity according to world region of origin, using a previously validated algorithm. The main outcome was incident onset of VTE during the period of observation. Risk ratios (RR) were calculated using Poisson regression models.

RESULTS

The incidence rate (IR) of VTE was lower among immigrants (0.87 per 1000 PY; 95% confidence interval [CI] 0.85-0.89) than nonimmigrants (1.59 per 1000 PY; 95% CI 1.56-1.61). Age- and sex-standardized IR were lower among East and South Asian immigrants. Compared to immigrants for predominantly White regions, age- and sex-specific RRs were consistently lower for East Asian (0.18-0.30) and South Asian (0.29-0.75) immigrants. In contrast, the RRs of VTE among Black (0.38-1.50), Latin American (0.29-1.25), Arab/Middle Eastern (0.44-1.08) and West Asian (0.31-1.16) immigrants were not significantly different from White immigrants.

CONCLUSIONS

In Ontario, the incidence of VTE is lower among immigrants compared to nonimmigrants. East and South Asian immigrants have a lower risk of VTE compared to White immigrants.

A prospective analysis for prevalence of complications in Thai nontransfusion-dependent Hb E/β-thalassemia and α-thalassemia (Hb H disease)

Recently, complications in patients with nontransfusion-dependent thalassemia (NTDT), in particular those with β-thalassemia intermedia (β-TI), were found to be significantly different from those in patients with transfusion dependent thalassemia (TDT), mainly β-thalassemia major (β-TM). However, this information is rather limited in other forms of NTDT. In this prospective study, adult Thai NTDT patients were interviewed and clinically evaluated for thalassemia related complications. Fifty-seven NTDT patients (age 18-74 years), 59.6% Hb E/β-thalassemia and 40.4% Hb H disease, were recruited; 26.4% were splenectomized. The most common complications were gallstones (68.4%), osteoporosis (26.3%), and pulmonary hypertension (15.8%). Splenectomy was associated with higher rate of gallstones and serious infection (P = .001 and .052, respectively), consistent with a multivariate analysis (RR = 9.5, P = .044, and RR = 15.1, P = .043, respectively). In addition, a higher hemoglobin level was inversely associated with gallstones in both univariate and multivariate analyses (P = .01 and .022, respectively). Serum ferritin was associated with abnormal liver function (P = .002). In contrast to the previous study, the prevalence of thrombosis was less common in our population (1.7%), probably due to differences in transfusion therapy, ethnicity, and underlying genotypes. For the first time, this prospective study provided the current prevalence of NTDT related complications in a Southeast Asian population with a different underlying genetic basis compared with previous studies. Although individual prevalence of each complication might differ from other studies, several important clinical factors such as splenectomy, degree of anemia, and iron overload seem to be determining risks of developing these complications consistently across different ethnicities.

Recurrent Miscarriage: Diagnostic and Therapeutic Procedures. Guideline of the DGGG, OEGGG and SGGG (S2k-Level, AWMF Registry Number 015/050)

Purpose

Official guideline of the German Society of Gynecology and Obstetrics (DGGG), the Austrian Society of Gynecology and Obstetrics (ÖGGG) and the Swiss Society of Gynecology and Obstetrics (SGGG). The aim of this guideline was to standardize the diagnosis and treatment of couples with recurrent miscarriage (RM). Recommendations were based on the current literature and the views of the involved committee members.

Methods

Based on the current literature, the committee members developed the statements and recommendations of this guideline in a formalized process which included DELPHI rounds and a formal consensus meeting.

Recommendations

Recommendations for the diagnosis and treatment of patients with RM were compiled based on the international literature. Specific established risk factors such as chromosomal, anatomical, endocrine, hemostatic, psychological, infectious and immunological disorders were taken into consideration.

Incidence of clinically suspected venous thromboembolism in British Indian patients

Introduction Venous thromboembolism (VTE) remains a major public health issue around the world. Ethnicity is known to alter the incidence of VTE. To our knowledge, there are no reports in the literature investigating the incidence of VTE in British Indians. The aim of this study was to investigate the rates of symptomatic VTE in British Indian patients in the UK. Methods Patients referred to our institution between January 2011 and August 2013 with clinically suspected VTE were eligible for inclusion in the study. Those not of British Indian or Caucasian ethnicity were excluded. A retrospective review of these two cohorts was conducted. Results Overall, 15,529 cases were referred to our institution for suspected VTE. This included 1,498 individuals of British Indian ethnicity. Of these, 182 (12%) had confirmed VTE episodes. A further 13,159 of the patients with suspected VTE were coded as Caucasian, including 2,412 (16%) who had confirmed VTE events. VTE rates were a third lower in British Indians with clinically suspected VTE than in the equivalent Caucasian group. The British Indian cohort presented with VTE at a much earlier age than Caucasians (mean 57.0 vs 68.0 years). Conclusions This study suggests that British Indian patients have a lower incidence of VTE and are more likely to present at an earlier age than Caucasians. There was no significant difference in VTE type (deep vein thrombosis vs pulmonary embolism) among the ethnic groups. Clinicians should be aware of variations within ethnicities but should continue to adhere to existing VTE prevention guidance.

Maternal Thrombophilia and Recurrent Miscarriage - Is There Evidence That Heparin is Indicated as Prophylaxis against Recurrence?

Background

Recurrent miscarriage, also referred to as recurrent spontaneous abortion (RSA), affects 1 – 5% of couples and has a multifactorial genesis. Acquired and congenital thrombophilia have been discussed as hemostatic risk factors in the pathogenesis of RSA.

Method

This review article was based on a selective search of the literature in PubMed. There was a special focus on the current body of evidence studying the association between RSA and antiphospholipid syndrome and hereditary thrombophilia disorders.

Results

Antiphospholipid syndrome (APS) is an acquired autoimmune thrombophilia and recurrent miscarriage is one of its clinical classification criteria. The presence of lupus anticoagulant has been shown to be the most important serologic risk factor for developing complications of pregnancy. A combination of low-dose acetylsalicylic acid and heparin has shown significant benefits with regard to pregnancy outcomes and APS-related miscarriage. Some congenital thrombophilic disorders also have an increased associated risk of developing RSA, although the risk is lower than for APS. The current analysis does not sufficiently support the analogous administration of heparin as prophylaxis against miscarriage in women with congenital thrombophilia in the same way as it is used in antiphospholipid syndrome. The data on rare, combined or homozygous thrombophilias and their impact on RSA are still insufficient.

Conclusion

In contrast to antiphospholipid syndrome, the current data from studies on recurrent spontaneous abortion do not support the prophylactic administration of heparin to treat women with maternal hereditary thrombophilia in subsequent pregnancies. Nevertheless, the maternal risk of thromboembolic events must determine the indication for thrombosis prophylaxis in pregnancy.

Impaired Coagulation Status in the Crohn's Disease Patients Complicated with Intestinal Fistula

Background:

Intestinal fistula is one of the common complications of Crohn's disease (CD) that might require surgical treatment. The clinical characteristics and outcomes of CD with intestinal fistula are much different from CD alone. This study was to investigate whether the coagulation status of CD is changed by intestinal fistula.

Methods:

Data were retrospectively analyzed for 190 patients with a definitive diagnosis of CD who were registered at the Jinling Hospital between January 2014 and September 2015. Baseline clinical characteristics and laboratory indices of initial admission and 7 days after intestinal fistula resections were collected. Student's t-test and the Wilcoxon rank-sum test were used to compare differences between the two groups.

Results:

Compared with CD patients without intestinal fistula, prothrombin time (PT) in patients with intestinal fistula was significantly longer (12.13 ± 1.27 s vs. 13.18 ± 1.51 s, P < 0.001 in overall cohort; 11.56 ± 1.21 s vs. 12.61 ± 0.73 s, P = 0.001 in females; and 12.51 ± 1.17 s vs. 13.37 ± 1.66 s, P = 0.003 in males). Platelet (PLT) count was much lower in intestinal fistula group than in nonintestinal fistula group (262.53 ± 94.36 × 10⁹/L vs. 310.36 ± 131.91 × 10⁹/L, P = 0.009). Multivariate logistic regression showed that intestinal fistula was significantly associated with a prolonged PT (odds ratio [OR] = 1.900, P < 0.001), a reduced amount of PLT (OR = 0.996, P = 0.024), and an increased operation history (OR = 5.408, P < 0.001). Among 65 CD patients receiving intestinal fistula resections, PT was obviously shorter after operation than baseline (12.28 ± 1.16 s vs. 13.02 ± 1.64 s, P = 0.006).

Conclusions:

Intestinal fistula was significantly associated with impaired coagulation status in patients complicated with CD. Coagulation status could be improved after intestinal fistula resections.

Relationship between neighborhood socioeconomic status and venous thromboembolism: results from a population-based study

Essentials Literature on socioeconomic status (SES) and incidence of venous thromboembolism (VTE) is scarce. We assessed neighborhood SES with VTE risk in a population of over 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. These findings are helpful to inform policy and resource allocation in health systems.

SUMMARY

Background The association between socioeconomic status and arterial cardiovascular disease is well established. However, despite its high burden of disability-adjusted life years, little research has been carried out to determine whether socioeconomic status is associated with venous thromboembolism. Objective To determine if neighborhood socioeconomic status is associated with venous thromboembolism in a population-based study from the Netherlands. Methods We identified all patients aged 15 years and older with a first event of venous thromboembolism from inhabitants who lived in the urban districts of The Hague, Leiden and Utrecht in the Netherlands in 2008-2012. Neighborhood socioeconomic status was based on the status score, which combines educational level, income and unemployment on a four-digit postal code level. Incidence rate ratios of venous thromboembolism were calculated for different levels of neighborhood socioeconomic status, with adjustments for age and sex. Results A total of 7373 patients with a first venous thromboembolism (median age 61 years; 50% deep vein thrombosis) were identified among more than 1.4 million inhabitants. Higher neighborhood SES was associated with lower incidence of VTE. In the two highest status score groups (i.e. the 95-99th and > 99th percentile), the adjusted incidence rate ratios were 0.91 (95% confidence interval [CI], 0.84-1.00) and 0.80 (95% CI, 0.69-0.93), respectively, compared with the reference status score group (i.e. 30-70th percentile). Conclusions High neighborhood socioeconomic status is associated with a lower risk of first venous thromboembolism.

Economic Evaluations of Thrombophilia Screening Prior to Prescribing Combined Oral Contraceptives: A Systematic and Critical Review

BACKGROUND

Combined oral contraceptives (COCs) increase the risk of venous thromboembolism (VTE), particularly among women with inherited clotting disorders. The World Health Organization classifies combined hormonal contraception as an "unacceptable health risk" for women with thrombogenic mutations but advises against universal thrombophilia screening before prescribing COCs given the low prevalence of thrombophilia and high screening costs.

OBJECTIVE

Through the lens of lifetime costs and benefits, this paper systematically and critically reviews all published economic evaluations of thrombophilia screening prior to prescribing COCs.

METHODS

We searched relevant databases for economic evaluations of thrombophilia screening before prescribing COCs. After extracting the key study characteristics and economic variables, we evaluated each article using the Quality of Health Economic Studies (QHES) and the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) instruments.

RESULTS

Seven economic evaluations of thrombophilia screening before prescribing COCs met our inclusion criteria. Only the two economic evaluations focusing exclusively on selective screening exceeded the 75-point threshold for high-quality economic studies based on the QHES instrument, whereas only one of these exceeded the 85% CHEERS threshold. Only three of the seven economic evaluations performed sensitivity analysis on key parameters. Most studies underestimated the benefits of thrombophilia screening by comparing one-time costs of genetic screening against benefits per person-year, thus implicitly assuming a 1-year duration of COC use, neglecting the long-term implications of VTE and/or neglecting the lifetime benefits of awareness of inherited thrombophilia.

CONCLUSION

Our review highlights the lack of methodologically rigorous economic evaluations of universal thrombophilia screening before prescribing COCs.

Epidemiology and risk factors for venous thromboembolism in lung cancer

PURPOSE OF REVIEW

Cancer is a strong risk factor for venous thromboembolism (VTE). In patients with lung cancer VTE is a significant cause for morbidity and mortality. The purpose of the review is to summarize the epidemiology of thrombotic events, risk factors for VTE and the clinical impact of VTE in patients with lung cancer.

RECENT FINDINGS

The rates of VTE in lung cancer patients vary according to different types of investigations, and reach 7 to 13%, including a significant number of unsuspected pulmonary emboli. Risk factors for VTE in patients with lung cancer can be basically divided into three categories: patient, tumor, and treatment related. In addition, a number of biomarkers have been described to be associated with VTE risk (e.g., D-dimer).

SUMMARY

Knowledge about the epidemiology, risk factors, and prognostic value of VTE in lung cancer could help to prevent thrombotic complications and improve management of patients with lung cancer.

Population-specific single-nucleotide polymorphism confers increased risk of venous thromboembolism in African Americans

INTRODUCTION

African Americans have a higher incidence of venous thromboembolism (VTE) than European descent individuals. However, the typical genetic risk factors in populations of European descent are nearly absent in African Americans, and population-specific genetic factors influencing the higher VTE rate are not well characterized.

METHODS

We performed a candidate gene analysis on an exome-sequenced African American family with recurrent VTE and identified a variant in Protein S (PROS1) V510M (rs138925964). We assessed the population impact of PROS1 V510M using a multicenter African American cohort of 306 cases with VTE compared to 370 controls. Additionally, we compared our case cohort to a background population cohort of 2203 African Americans in the NHLBI GO Exome Sequencing Project (ESP).

RESULTS

In the African American family with recurrent VTE, we found prior laboratories for our cases indicating low free Protein S levels, providing functional support for PROS1 V510M as the causative mutation. Additionally, this variant was significantly enriched in the VTE cases of our multicenter case-control study (Fisher's Exact Test, P = 0.0041, OR = 4.62, 95% CI: 1.51-15.20; allele frequencies - cases: 2.45%, controls: 0.54%). Similarly, PROS1 V510M was also enriched in our VTE case cohort compared to African Americans in the ESP cohort (Fisher's Exact Test, P = 0.010, OR = 2.28, 95% CI: 1.26-4.10).

CONCLUSIONS

We found a variant, PROS1 V510M, in an African American family with VTE and clinical laboratory abnormalities in Protein S. Additionally, we found that this variant conferred increased risk of VTE in a case-control study of African Americans. In the ESP cohort, the variant is nearly absent in ESP European descent subjects (n = 3, allele frequency: 0.03%). Additionally, in 1000 Genomes Phase 3 data, the variant only appears in African descent populations. Thus, PROS1 V510M is a population-specific genetic risk factor for VTE in African Americans.

Drug Treatment of Venous Thromboembolism in the Elderly

Half of all patients with acute venous thromboembolism are aged over 70 years; they then face the added hazard of an age-related increase in the incidence of major bleeding. This makes it even more important to weigh the balance of benefit and risk when considering anticoagulant treatment and treatment duration. Traditional treatment with a heparin (usually low molecular weight) followed by a vitamin K antagonist such as warfarin is effective but is often complicated, especially in the elderly. The direct-acting oral anticoagulants (DOACs), i.e. the thrombin inhibitor dabigatran and the factor Xa inhibitors rivaroxaban, apixaban and edoxaban, are given in fixed doses, do not need laboratory monitoring, have fewer drug-drug interactions and are therefore much easier to take. Randomised trials, their meta-analyses and 'real-world' data indicate the DOACs are no less effective than warfarin (are non-inferior) and probably cause less major bleeding (especially intracranial). It seems the relative safety of DOACs extends to age above 65 or 70 years, although bleeding becomes more likely regardless of the chosen anticoagulant. Renal impairment, comorbidities (especially cancer) and interventions are special hazards. Ways to minimise bleeding include patient selection and follow-up, education about venous thromboembolism, anticoagulants, drug interactions, regular checks on adherence and avoiding needlessly prolonged treatment. The relatively short circulating half-lives of DOACs mean that time, local measures and supportive care are the main response to major bleeding. They also simplify the management of invasive interventions. An antidote for dabigatran, idarucizumab, was recently approved by regulators, and a general antidote for factor Xa inhibitors is in advanced development.

A multicenter phase 2 study of pomalidomide plus dexamethasone in patients with relapsed and refractory multiple myeloma: the Japanese MM-011 trial

Background

The immunomodulatory agent pomalidomide in combination with low-dose dexamethasone has demonstrated efficacy and safety for the treatment of relapsed and refractory multiple myeloma (RRMM) in phase 2 and 3 trials. However, these trials enrolled very few Asian patients.

Methods

This phase 2 study investigated pomalidomide plus low-dose dexamethasone in 36 Japanese patients with RRMM after ≥2 prior therapies.

Results

Patients enrolled in the study had a relatively high disease burden (81 % Durie–Salmon stage II or III) and were heavily pretreated (median, 6.5 prior antimyeloma regimens). The overall response rate was 42 % (1 patient with complete response and 14 with partial response), with an additional 44 % (16 patients) achieving stable disease (SD). Response rates in patients aged ≤65 years and >65 years were 47 and 35 %, respectively. None of the five patients with extramedullary disease achieved a response, with three of them maintaining SD of short duration. Median progression-free survival was 10.1 months after a 7.7-month median follow-up, and the median overall survival was not reached. The most frequent grade ≥3 adverse events (AEs) were neutropenia (64 %), anemia (42 %), and thrombocytopenia (31 %). The most frequent nonhematologic grade ≥3 AEs were pneumonia and decreased appetite (8 % each). Adverse events in patients aged >65 years were similar to those in patients aged ≤65 years, except for a higher rate of grade ≥3 pneumonia.

Conclusions

Collectively, the results of this study demonstrate that pomalidomide plus low-dose dexamethasone is an effective and safe treatment for Japanese patients with RRMM, although careful attention needs to be paid to serious infections.

Trial registration: Clinicaltrials.gov NCT02011113

Genetic association of PROC variants with pulmonary embolism in Northern Chinese Han population

To evaluate SNPs (single nucleotide polymorphism) in PROC (protein C gene) associated with pulmonary embolism (PE) susceptibility in North Chinese Han population. A case-control study design was used, and patients with PE and healthy participants were enrolled from the Emerging Department of the several hospitals in Weifang, Shandong, China. SNPs in PROC were genotyped using Mass ARRAY system. The allele frequency of rs199469469 was significantly different between PE patients and the control [OR (95 % CI) = 5.00 (1.66-15.12), P = 0.004], and the difference remained significantly after controlling for age and gender [OR (95 % CI) = 5.34 (1.47-19.39), P = 0.011). The G(del)G in the haplotype includes rs1799809|rs199469469|rs2069928 was of a significantly difference (P = 0.016) among PE patients and the controls, and remained significant (P = 0.015) after adjustment for age and sex. Our study reports that PROC SNPs (rs199469469) might be associated with PE susceptibility, with the G allele of rs199469469 serving as the protective factors for incidence of PE. These findings may contribute to the understanding and primary prevention of PE.

Age-specific onset and distribution of the natural anticoagulant deficiency in pediatric thromboembolism

BACKGROUND

The early diagnosis of inherited thrombophilia in children is challenging because of the rarity and hemostatic maturation.

METHODS

We explored protein C (PC), protein S (PS), and antithrombin (AT) deficiencies in 306 thromboembolic patients aged ≤20 y using the screening of plasma activity and genetic analysis.

RESULTS

Reduced activities were determined in 122 patients (40%). Low PC patients were most frequently found in the lowest age group (0-2 y, 45%), while low PS or low AT patients were found in the highest age group (16-20 y; PS: 30% and AT: 20%). Genetic study was completed in 62 patients having no other causes of thromboembolism. Mutations were determined in 18 patients (8 PC, 8 PS, and 2 AT genes). Six of eight patients with PC gene mutation were found in age 0-2 y (75%), while six of eight patients with PS gene mutation were in 7-20 y. Two AT gene-mutated patients were older than 4 y. Four PC-deficient and two PS-deficient patients carried compound heterozygous mutations. All but one PC gene-mutated patient suffered from intracranial thromboembolism, while PS/AT gene-mutated patients mostly developed extracranial venous thromboembolism.

CONCLUSION

Stroke in low PC infants and deep vein thrombosis in low PS/AT school age children could be targeted for genetic screening of pediatric thrombophilias.

Recurrent Miscarriage: Diagnostic and Therapeutic Procedures. Guideline of the DGGG (S1-Level, AWMF Registry No. 015/050, December 2013)

Purpose: Official guideline coordinated and published by the German Society of Gynecology and Obstetrics (DGGG). Aim of the guideline was to standardize the diagnosis and treatment of patients with recurrent miscarriage (RM). Recommendations were proposed, based on the current national and international literature and the experience of the involved physicians. Consistent definitions, objective assessments and standardized therapy were applied. Methods: Members of the different involved societies developed a consensus in an informal process based on the current literature. The consensus was subsequently approved by the heads of the scientific societies. Recommendations: Recommendations for the diagnosis and treatment of patients with RM were compiled which took the importance of established risk factors such as chromosomal, anatomical, endocrine, hemostatic, psychological, infectious and immunological disorders into consideration.

Characteristics and Risk Factors of Cancer Associated Venous Thromboembolism

INTRODUCTION

The objective of this study was to examine the differences in commonly associated characteristics and risk factors of venous thromboembolism (VTE) between patients with and without cancer in a VTE population.

MATERIALS AND METHODS

Uniform data were collected for patients with a diagnosis of VTE obtaining care at CDC funded Thrombosis Network Centers. Patient characteristics and risk factors were compared in VTE patients with and without cancer. Logistic regression was used to calculate the unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) to assess patient characteristics and thrombotic risk factors more frequently identified among VTE patients with cancer compared to those without cancer.

RESULTS

Between August 2003 and April 2011, 3,115 adult patients with a diagnosis of VTE including 189 (6.1%) patients with active cancer participated in the multi-site thrombosis registry. VTE patients with cancer had a higher prevalence of PE and DVT in unusual sites compared to those without cancer. Thrombophilia was more common among VTE patients without cancer than those with cancer (25.1% vs 10.6%, p<0.001). In adjusted analysis, age group≥45years (OR =5.20, 95% CI, 3.30, 8.18), surgery (OR =1.86, 95% CI, 1.19, 2.91), and hypertension (OR =1.66, 95% CI, 1.15, 2.40) were the VTE risk factors more commonly found among VTE patients with cancer.

CONCLUSION

The study identified several thrombotic risk factors more likely to be found with cancer associated VTE, which may help to characterize at risk cancer patients and to develop prevention and management strategies in this population.

Factors contributing to APC-resistance in women with recurrent spontaneous miscarriages: Indian perspective

Phenotypic resistance to APC is a complex mechanism associated with increased risk of venous thrombosis in women with recurrent spontaneous abortions. The primary aim of this prospective case control study was to find out the frequencies of different congenital and acquired thrombophilic factors predisposing to APC resistance and to evaluate the strength of their association with recurrent pregnancy losses. FV Leiden accounted for around 40% of all APCR positive patients and the difference in the group frequencies compared with controls, was found to be statistically significant (p=0.001). 18.33% (11/60) FV Leiden-negative APC-resistant patients had

FVIII

c values exceeding 95th percentile of the control population (145IU/dL), as compared to 3% in the control group (p=0.001). Mean FVIII level in control subjects was 118±14.0IUdL(-), compared with 127.7±31.2IUdL(-) in the patient group (p=0.009). Apart from FVIII, only the anti-phospholipid antibodies showed a statistically significant association with APCR phenotype (p=0.028), unlike other thrombophilic factors such as Protein C, Protein S, FV levels, HR2 haplotype or other rarer FV variants. The strong positive association of FVL mutation, anti-phospholipid antibodies and elevated FVIII levels with APCR phenotype calls for incorporating them as first line investigations in patients with recurrent spontaneous miscarriages with APCR positivity.

The Contributions of Thrombophilic Mutations to Genetic Susceptibility to Deep Venous Thrombosis in Iraqi Patients

BACKGROUND AND AIMS

There is a paucity of data on the contribution of various thrombophilic mutations to the development of venous thrombosis in Iraqi patients. Therefore we designed a study to assess the frequencies of known thrombophilic mutations in this population.

METHODS

100 consecutive Iraqi patients with color Doppler confirmed deep venous thrombosis of the lower extremities and 100 age- and sex-matched healthy controls were enrolled in the study. Their DNAs were tested by multiplex polymerase chain reaction (PCR) followed by reverse hybridization for factor V Leiden (FVL), the prothrombin (PT) G20210A SNP, and the MTHFR C677T SNP. The factor V A4070G mutation was assessed by restriction fragment length polymorphism-PCR.

RESULTS

The prevalence of FVL was 13% in patients versus 2% in controls (odd ratios [OR] 7.3; p=0.007). Patients with recurrent thrombosis also had a significantly higher frequency of Factor V Leiden (OR 8.4, p=0.0007). The prothrombin G20210A, SNP, the factor V A4070G SNP, and the MTHFR 677 TT genotypes were present among patients at 5%, 9%, and 11%, respectively, and among controls at 2%, 6%, and 6%; none of these single mutation prevalence differences were significant. Interestingly, however, when these polymorphisms were studied in aggregate we found that 24% of patients had two or more thrombophilic alleles, compared to only 8% of the controls (OR 3.6; p=0.002). This subgroup included significantly more patients with proximal (p=0.007) and recurrent thrombosis (p=0.012), as well as younger patients (≤40 years) (p=0.026).

CONCLUSION

Two or more thrombophilic alleles, as well as FVL on its own, were both significantly associated with an increased risk of venous thrombosis and recurrence in Iraqi patients. Single thrombophilic mutations on their own were not associated with an increased risk.

Ethnic diversity in the genetics of venous thromboembolism

Genetic susceptibility is considered as a crucial factor for the development of venous thromboembolism (VTE). Epidemiologic and genetic studies have revealed clear disparities in the incidence of VTE and the distribution of genetic factors for VTE in populations stratified by ethnicity worldwide. While gain-of-function polymorphisms in the procoagulant genes are common inherited factors in European-origin populations, the most prevalent molecular basis for venous thrombosis in Asians is confirmed to be dysfunctional variants in the anticoagulant genes. With the breakthrough of genomic technologies, a set of novel common alleles and rare mutations associated with VTE have also been identified, in different ethnic groups. Several putative pathways contributing to the pathogenesis of thrombophilia in populations of African-ancestry are largely unknown, as current knowledge of hereditary and acquired risk factors do not fully explain the highest risk of VTE in Black groups. In-depth studies across diverse ethnic populations are needed to unravel the whole genetics of VTE, which will help developing individual risk prediction models and strategies to minimise VTE in all populations.

Prevalence of JAK2V617F mutation in deep venous thrombosis patients and its clinical significance as a thrombophilic risk factor: Indian perspective

Venous thromboembolism is known to be a complex interaction of genetic and acquired factors leading to thrombosis. JAK2V617F mutation is believed to contribute to a thrombophilic phenotype, possibly through enhanced leukocyte-platelet interactions in myeloproliferative neoplasms (MPNs). Several studies have focused on the importance of screening for JAK2V617F mutation in patients with splanchnic venous thrombosis (VT) for the detection of nonovert MPNs. The role of JAK2V617F mutation in VT outside the splanchnic region is still widely unsettled. The primary aim of this study was to find out the prevalence of JAK2V617F mutation in patients with deep venous thrombosis (DVT), its clinical significance as a prothrombotic risk factor, and its possible interactions with other genetic thrombophilic risk factors. A total of 148 patients with idiopathic, symptomatic DVT were evaluated. Median age of presentation was 32 years (range 15-71 years) with a sex ratio of 1.3:1. Overall, the most common genetic prothrombotic factor was factor V Leiden mutation, found in 10.8% (16 of 148) of patients who also showed strong association with increased risk of thrombosis (odds ratio 5.94, confidence interval 1.33-26.4, P = .019). Deficiencies in protein C, protein S, and antithrombin were seen in 8 (5.4%), 10 (6.7%), and 8 (5.4%) patients, respectively. It was observed that the frequency of JAK2V617F mutation was lower in Indian patients, and it also showed weaker association with risk of thrombosis, at least in cases of venous thrombosis outside the splanchnic region.

Influence of acquired and genetic risk factors on the prevention, management, and treatment of thromboembolic disease

Prevention, management, and treatment of venous thromboembolism requires understanding of the epidemiology and associated risk factors, particularly in recognizing populations warranting prophylaxis, in evaluating patients with high risk situations, and in determining the duration of anticoagulation required to minimize recurrent thrombosis and to avoid postthrombotic syndrome. The present paper reviews recent advances concerning acquired and genetic risk factors for venous thrombosis, analyses individual risks related to age, and focuses on thrombotic genetic risk factors and the synergistic gene-environment and gene-gene interactions and their importance in the management and treatment of venous thromboembolic disease.

Review article: Venous thromboembolism after total joint replacement

Venous thromboembolism can occur in up to 84% of cases following total joint replacement. It can result in pain, swelling, chronic post-thrombotic syndrome, and pulmonary embolism. Its prevention is vital to the success of the surgery. To achieve a safe and effective prophylaxis, a combination of mechanical and pharmacologic agents should be used. New generation of thromboprophylactic agents target different factors of the coagulation pathway.